The Effect of Temperature on Dyeing Cotton with Indigo. Charlotte Zelle and Samantha Pilicer. The purpose of this lab was to use indigo dye formed by two different methods, on cotton, at three different temperatures. Fermentation and the sodium hydrosulfite reduction of indigo were the methods used to form indigo dye in used on the cotton swatches. Principles of fermentation, chemical reduction, solubility, and temperature sensitivity were applied. Found in these results was that the sodium hydrosulfite dye vat resulted in the most effective cotton dyeing method regarding indigo. The fermentation method was less effective which can probably be attributed to incomplete fermentation. In conclusion, the results obtained in this study of indigo dyeing suggest that at lower temperatures, sodium hydrosulfite reduced indigo vat dye yields more effective dyeing and that the fermentation method in general was less effective overall. The detrimental environmental impact of fermentation is not as great as that of the sodium hydrosulfite vat dye, so the environmental effects and effectiveness should weighed in textile dyeing.
Key terms: fermentation, chemical reduction, indigo, cotton, textile dyeing, solubility.


Audacity:

Apparatus:


Pressurized Stopper:
pressure_flask.jpg

Summary Graphics:
GRAPHIC.JPG
Summary Table: Indigo Dye Results

#1
#2
#3
#4
#5
#6
#7
Temp. Overnight
Room Temp.
Room Temp.
About
43 degrees C
About
43 degrees C
Refrigerator
0.5 degrees C
Room temp
Incubator
41.5 degrees C
Extra Sodium Hydrosulfite Added
None
21mL
7mL
None
7mL


Other Notes
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Heated (to 49 degrees C) only after the first 7mL
Heated for the whole time adding extra 7mL
---
Heated to 80 degrees C!! Then added 7mL.
Added yeast a few times, and put in incubator a few times. BUT always blue. Then tried to dye with it.
Added yeast a few times, and put in incubator a few times. BUT always blue. Then tried to dye with it.
1-4 (From Lightest to darkest)
4
6
5
3
7
1
2


Sources:
Doğan D., Türkdemir H. 2005. Electrochemical oxidation of textile dye indigo. Journal of Chemical Technology and Biotechnology. 80: 916-923.

Meksi N., Kechida M., Mhenni F. 2007. Cotton dyeing by indigo with the borohydride process: Effect of some experimental conditions on indigo reduction and dyeing quality. Chemical Engineering Journal. 131: 187-193.